Data traffic in mobile telecommunications networks is continually increasing. Consequently, operators are employing heterogeneous access networks that utilise multiple radio access technologies (RATs) in order to provide greater capacity, particularly in high traffic areas and areas that otherwise have poor network coverage.
Typically, the radio access technologies utilised as part of these heterogeneous access networks include UMTS Radio Access Network (UTRAN) and an Evolved UTRAN (E-UTRAN), and Wi-Fi/WLAN. For example, FIG. 1 illustrates schematically a simplified example of a heterogeneous network 1 that comprises a 3rd Generation Partnership Project (3GPP) radio access node (RAN) 2 and a Wi-Fi RAN 3 suitable for implementing the methods described herein. The 3GPP RAN 2 includes a number of 3GPP radio nodes 4. For example, if the 3GPP RAN was a UTRAN, then these radio nodes would be NodeBs and Radio Network Controllers (RNC). By way of further example, if the 3GPP RAN was an E-UTRAN, then these radio nodes would be eNodeBs. The 3GPP RAN 2 is connected to a mobile core network 5. The Wi-Fi RAN 3 includes a number of Wi-Fi/WLAN APs 7 that can be connected to a Wi-Fi/WLAN Access Controller (AC) 8. The Wi-Fi/WLAN AC 8 can control each of the Wi-Fi/WLAN APs 7 and assists in authentication of a mobile station/user terminal that wants to associate with/attach to the Wi-Fi RAN/WLAN 3.
If the heterogeneous access network comprises a UTRAN, an E-UTRAN, and a Wi-Fi RAN/WLAN then both the UTRAN and E-UTRAN standards are defined by the 3rd Generation Partnership Project (3GPP). Within 3GPP in order to enable the coverage and/or performance of a network to be monitored a UE may support Minimization of Drive Testing (MDT). A UE implementing MDT logs radio measurements relating to the network. The log may also include the location of the UE when the measurement was made. These logs are provided to one or more nodes within the network upon request and can be used in order to tune the parameters of the network or to address a problem within a network.
MDT measurements may be made when the UE is connected to a 3GPP cell and be reported directly back to the eNodeB or Radio Network Controller (RNC) dependent upon the configuration in the UE. Alternatively the MDT measurements may be logged whilst the UE is in Idle mode and not actively connected to the network. In this instance the UE will log the information and the information will be transmitted to the eNodeB or RNC when the UE next connects to the 3GPP network.
However, there is no such provision within the Wi-Fi RAN/WLAN standards defined by the Institute of Electrical and Electronics Engineers (IEEE). Thus a WiFi/WLAN RAN has no access to information about the network.